"Our system is a little more forgiving," Scott Prevost, general manager of Powerset, said in an interview on Sunday. "It is not looking for hard-word matches. We are not searching for exact words, but concepts," he said.

The 2-1/2-year-old start-up licensed natural language processing technology and related machine processing methods developed over three decades at the Xerox PARC research centre in Silicon Valley to create new consumer Web search services.

With tacit approval of the non-profit Wikimedia Foundation, the organization behind the Wikipedia, Powerset officials said they are hosting a copy of Wikipedia's 2.5 million English-language entries on its own computers. This lets Powerset make links across the breadth of Wikipedia data.

"What Powerset is doing is offering readers a natural-language search interface, and we think that is an interesting experiment," Mike Godwin, Wikimedia Foundation's general counsel, said in response to an e-mailed question about how the two organizations would work together.

In addition to Wikipedia, Powerset's new service also searches a related database called Freebase created by MetaWeb, another Web search start-up.

After decades of research and debate, natural language processing is finally poised to go mainstream, predicted Barney Pell, co-founder and chief technology officer.

"2008 is the year that semantic and linguistic technologies cross over into widespread consumer use," he said.